RFR(XS) 8032894: Remove dead code in Pressure::lower (original) (raw)

Vladimir Kozlov vladimir.kozlov at oracle.com
Wed Jan 29 10:53:24 PST 2014

What is initial state of _current_pressure, _high_pressure_limit, _final_pressure? How we can get case (_current_pressure == _high_pressure_limit)? May be we should replace the code with assert:

assert(_current_pressure <= _final_pressure

Thanks, Vladimir

On 1/29/14 4:09 AM, Niclas Adlertz wrote:

Hi all,

When building the physical IFG, we step backwards in each block, and remove things that are defined from the LIVEOUT, (and lower the current pressure) and add input to the LIVEOUT (and raising the current pressure). Each time we lower or raise the current pressure, we check if it's bigger than the current maximum pressure, known as finalpressure. However the finalpressure can never increase when removing definitions (i.e. lower the current pressure) so the check for a new finalpressure in Pressure::lower is useless. webrev: http://cr.openjdk.java.net/~adlertz/JDK-8032894/webrev00/ bug: https://bugs.openjdk.java.net/browse/JDK-8032894 Kind Regards, Niclas Adlertz

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